omega -Chloroalkyl biliverdins, prepared in three steps from 8-unsubstituted dipyrrinones in 70-80% overall yields, were reduced by sodium borohydride to provide the corresponding omega -chloroalkyl bilirubins in high yields. Upon treatment of the omega -chloroalkyl biliverdins with sodium hydroxide in ethanol, C12-N22 bridged biliverdins were obtained in high yields.